Method of fabricating felts and felt materials



Patented Oct. 16,1928.

UNITED STATES PATENT OFFICE.

HYMAN STEIN AND WILLIAM E. AUSTIN, OF NEW YORK,AND IRVING LIEBOWITZ, OF BROOKLYN, NEW YORK, ASSIGNORS TO STEIN FUR DYETNG 00., INQ, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

METHOD OF FABRICATING FELTS AND FELT MATERIALS.

No Drawing.

either before, during, or after the steps of the process for rendering the hairor other animal fibers, or the fur skins carrying such hair, suitable for felting. Our invention may be applied with particular success to the treatment of dark-colored animal fibers, particularly dark colored hair and fur skins carrying the same to render the same suitable for the felting operation and to derive from the same a feltable fiber of a light color very suitable for dyeing and for felting into a felted fabric.

Our invention aims to devise methods of the general character described above which are simple to practice, which are economical in the matter of the time, labor, material and equipment required for their practice, and which yield intermediate and end products of superior qualities for the intended purpose. Our invention, so far as the same relates to such products in the various stages of their production, is claimed in a copending application of ours filed of even dateherewith and entitled Felts and felt materials and articles, such as hats and hat bodies, made of the same.

. In the accompanying specification we shall describe illustrative embodiments of the processes of the persent invention. It is, however, to be clearly understood that our invention is not limited to the specific forms thereof herein described for purposes of illustration only. Before describing in detail the aforesaid illustrative embodiments of the present invention, it may be desirable briefly to point out certain disadvantages of the prior art so far as'the same relates to the field of the present invention. Hitherto it has been proposed, for example, to carrot animal fibers, such as fur skins and the like or the hair of such skins, to render the same suitable for felting operations, by treating such skins or the hair of the. same with an acid solution of nitrate of mercury. This treatment, if

Application filed February 10, 1925 Serial No. 8,306.

used by itself for the entire carroting operation, tends to weaken and otherwise hurt the hairs or equivalent fibers.

Furthermore, where it is desired to obtain a light colored mass of feltable hairs or other animal fibers, if the hair is bleached first, the bleaching operation generally tends to weaken the hair to such an extent that the subsequent carroting operation, tending further to weaken the hair, would tend often to render the same quite unfit for the subsequent felting operation. 'It has, therefore, not been feasible to make a li ht colored mechanically desirable feltable fi er from a dark colored skin by the usual bleaching and carroting operations.

On the other hand, if the hair or equivalent animal fibers are first carroted, as by means of the treatment with the acid solu-- tion of nitrate of mercury referred to above,

this treatment would tend to render the subsequent bleaching operation imperfect and otherwise quite unsatisfactory. In any event, both the carroting and the bleaching operations as hitherto conducted, in whatever order they have been carried out, would both singly and conjointl tend to considerably weaken and otherwise impair the structure and appearance, as well as the felting qualities, of the fur, hair or other fibers to which the treatments of the prior art might be applied.

We have discovered a new method of carroting or treating fur skins, hair and other animal fibers to render the same suitable for subsequent felting operations. Our new carroting process is characterized by the fact that it does not substantially hurt the fur, hair or other fibers treated in accordance With such process. The carroting operation of the present invention may moreover be very effectively combined with a bleaching operation whereby dark colored skins or the hair thereof may be ultimately obtained in a condition ideally suited for felting or already felted in a very light color,

in which condition the feltable mass or the felted product is admirably suited for dyeing any light or other suitable color. In one operation which at the same time completes the carroting operation and thus yields a bleached fiber admirably suited for felting. Referring now to the aforesaid illustrative embodiments of the methods of the present invention, we take first any suitable fur skin or the hair of such skin, or any other suitable animal fiber which it is desired to convert into a feltable fiber. Preferably we treat a fiber which is dark and which we desire to bleach into a light colored, readily feltable fiber. For example, we may take rabbit skins of a dark color and treat the same with great success in accordance with the principles of the present invention. g

It may here be stated that the principles of the present invention may be applied with almost equal success ether to the fur skin itself, such as. the dark or other colored rabbit skins referred to, or to the hair obtained from such skins. It may also here be stated that in accordance with the principles of the present invention, neither the fur skins nor the hair derived from the same need first be washed or killed in an alkaline solution, such as a solution of sodium carbonate. However, in some instances, this washing operation, which ordinarily required from about two to about three hours,

may be employed, although We prefer to dispense with the same in most instances.

We now treat the fur skins or the hair of the same, referred to above, preferably the (ill dark or other colored-rabbit skins or hair from such skins, with a suitable carroting agenti preferably a metallic compound car- 'roting agent, but preferably only to the point of partial completion of the carroting step. For example, I may treat the fur skins or other animal fibers in accordance with the principles of the present invention with nitrate of mercury, obtained, for'example, by the solution of metallic mercury in nitric acid, thus obtaining an acid solution of nitrate of mercury. This treatment is preferably continued only to the point of partial completion of the carroting opera: tion, as by using on l-y one-half, or only twothirds or three-fourths, or' any suitable amount of the acid solution of the nitrate of mercury or equivalent metallic or other carroting agent, short'of the amount which would be required for the completion of the carroting operation. This is very desirable, since the subsequent bleaching operation serves, at the same time, to complete the carroting operation, all of which is done in accordance with the principles of the present invention without destruction of the hair or other'animal fibers and without in any way impairing1 their ultimate felting qualities. In fact, t e felting qualities of animal fibers treated in accordance with the principles of the present invention are su perior to those of ordinary fibers treated in accordance with the methods hitherto em-' ployed for this purpose.

We now treat the partially carroted fibers,prior to the subsequent bleaching and completion of the carroting process, with a protective agent, generally a reducing compound, preferably of mineral origin, such as a ferrous compound, for example, ferrous sulphate. In some way, the reasons for which are at present not understood by us, such protective agent, while permitting the bleaching or decolorizin action to proceed under the action of the bleaching agent with remarkable rapidity, protects the leather of the fur skin and the hair of the same from any destructive or weakening effect of the bleaching agent.

For instance, decolorizing or' bleaching of fur skins or the like takes place in accordance with the principles of the resent invention under the action of a bleac ing agent such as hydrogen peroxide, for example, within a short time, as from about one to about four hours. This is contrasted with the twenty-four to seventy-two hours hith erto required for bleaching fur skins by the methods hitherto commonly employed. At the same time the leather and hair of the skins and the fibers of the hair or other animal fibers bleached in accordance with the principles of the present invention, will be found to be in fine condition, with their strength, texture and lustre substantially unimpaired. At the same time, we have discovered that the carroting operation is completed by what we have thus far termed the bleaching operation. It appears that the hydrogen peroxide or equivalent bleaching agent acts as a non-metallic carroting agent to complete the carroting operation only partially completed by the acid solution of nitrate of mercury or equivalent metallic carroting agent.

While we do not Wish to be limited to any particular theory or explanation as to why this remarkable, unexpected and commercially valuable result is obtained, our present explanation is that the presence on or in the fibers of the fur skins or the like of the mineral reducing agent or its equivalent, the effectiveness of which appears not to be diminished bythe presence of the nitrate of mercury or other metallic carroting agent,

prevents too violent an action of the hydrogen peroxlde or equivalent bleaching agent. At the same time, the hydrogen peroxide or equivalent bleaching agent acts to complete the carroting operation and the ultimate product is a fiber light in color and remarkably well adapted for subsequent felting operations. In fact, the presence of the metallic protective agent, such as the ferrous compound referred to,- or its equivalent, especially in the presence of the nitrate of mercury or equivalent metallic carroting agent, not only protects the leather and the hair of thefur skins or other animal fibers froin destructive or weakening action, but at the same time actually accelerates the desired decolorizing or bleaching action and the completion of the carroting operation, so that the combined bleaching and carroting operation take only from about one to about four hours, instead of the twentyfour to seventy-two hours hitherto required for the imperfect or even destructive bleaching methods ashitherto practiced.

Since. the protective agent and bleaching accelerator in accordance with the principles of the present invention, generally com rises a reducing agent or compound, prefera ly of mineral origin, such as a ferrous compound, for example, ferrous sulphate, which would tend to be oxidized more or less readily on exposure to the air, we prefer to add to the protective agent preferably before the same is applied to the fur skin or the like, prior to the bleaching and carrot-ing operation, a stabilizing agent. The purpose of the stabilizing agent is to stabilize the protective agent and to prevent too rapid oxidation or deterioration of the same. Where, as is preferred, ferrous sulphate is used for the protective agent, we prefer to use for the stabilizing a ent ammonium chloride. The fur skins or t e like, after having been treated with'a solution of the protective compound which may or may not'contain therein the stabilizing agent, are thereafter subjected 'to the combined bleaching and carroting operation, after which they may be dyed in any of the light orother shades such as can at the present time be produced only by dyeing natural white or other light colored skins or other animal fibers.

The following is a specific example of one mode of applying the method of the present invention, it being understood, however, that the following description is given merely by wa not limited to the specific details of the following illustrative example:

The dark colored rabbit skins, preferably without being first washed or killed? in an alkaline solution, such as a solution of .sodium carbonate, which washing operation ordinarily requires from about two to about three hours, are immersed in an acid solution of nitrate of mercury in an amount sufiicient only partially to carrot such skins or like animal fibers. only one-half, oreven, as much as twothirds or three-fourths, of the usual amount of acid solution of nitrate of mercury is em-' ployed so that the carroting operation at this stage is only partially completed.

The artially carroted skins or other animal bers are then rinsed and thoroughly hydro-extracted. The skins are then immersed in .a solution of the protective agent,

of illustration and that the process 'is- For example,

tion of ferrous sulphate of a strength of from about 0.5 to about 5.0 per cent of the solid crystallized ferrous sulphate, by weight. Such a solution may or may not contain the stabilizing agent. If a stabilizing agent, such as ammonium chloride, is used, we prefer to use it in an amount approximately proportionate to the amount of ferrous sulphate used and equalling from about 0.5 to about 5.0 per cent of ammonium chloride, by weight.

f The fur skins or the like, after having been soaked for from about 8 to about 12 hours in the solution of the protective agent, with or without the addition of the stabilizing agent, are then rinsed and hydro-extracted. The treatment apparently impregnates or fills'the voids and lnterstices of the fibers with the solution of protective agent. The fur skins thus treated are now immersed in a solution of hydrogen peroxide or equivalent bleaching agent. However, in place of hydrogen peroxide, we may use other bleaching agents, particularly sodium eroxide or sodium perborate, which yiel hydrogen peroxide in solution in the presence of. certain liberating agents, generally of an acid character. The amount of hydrogen peroxide used may vary from about five (5.0) to about one hundred (100.0) per cent by volume of a three (3.0) per cent solution of hydrogen peroxide. We prefer that the temperature at which thebleaching or 'decolorizing operation is carried out shall be between 60 and 100 F.

The skins or hair are subjected to the action of the bleaching and carroting agent until they have been sufliciently decolorized.

' The bleached and now completely carroted ever, subject the. bleached ordecolorized 1'15 skins or hair to the usual dyeing operation of washing and mordanting, and .then dyeing the washed and mordanted skins or hair in accordance with the practice hitherto lgenerally employed for dyeing furs and air.

It may here be stated that a metallic salt or salts may be added to the solution of the protective agent, with or without the stabilizing agent, provided such metallic salt or salts are compatible with the ferrous sulphate or equivalent protective agent. In. such. a case, the combined decolorizing and carroting process proceeds in exactly the same way as before, while the additional. salt or salts may act a mordant for the subsequent dyeing process where a mordant is desired or needed for this purpose. It may here also be stated that while, in accordance with our experience up to the present time, the foregoing process may be successfully applied to all dark colored furs, the concen: tration of the reagents employed and the methods of subjecting the fur skins and the like to the various partial carroting, protective, and combined bleaching and carroting operations, as well as the subsequent mordanting and dyeing operations, will depend very largely upon the nature. of the skins or other animal fibers being treated, the factors of temperature, concentrations, lengths of time of treatment, and the like, or any particular kind of animal fiber'or the like, being readily determined by trial and experiment. i It may here be stated that in addition to the mineral protective agent, such as the ferrous sulphate, with or without the addition of the stabilizing agent, the solution for giving the fur skins or the like their protective treatment for the subsequent combined bleaching and carroting operation may contain other compatible metal salts, as well as suitable protective colloids, such as glue gelatin, or the like, generally in relatively small amounts. It may here also be stated that the methods described above may be applied with almost equal success in the treatment of skins which have already been dyed, either a dark or a light color, and whether satisfactorily or not, but preferably skins which have been dyed by the use of a mordant consisting of a ferrous compound, such as ferrous sulphate, or an equivalent substance, thus producing from the previously dyed skins and hair' the superior products described above.

The advantages of the foregoing embodiments of the processes of the present invention are numerous and of great practical importance and may be briefiysummarized as follows: In the first place the foregoing embodiments of the; present invention enable the carroting. operation to be economically and quickly effected, with little weakening of the fibers, while yielding fibers which are readily feltable and which may be compasted to yield a remarkably fine felt, both as to texture, strength and color. Especially where dark colored hair or other fibers are employed, the process enables a feltable mass of fibers to be obtained from 'such dark colored skins or hair in a very light color ordinarily obtainable only by the treatment of naturally white or light colored skins or hair derived from. the same. By combining the bleaching operation with the completion of the carroting operation, as

above described, a ready control of the carroting operation and of the bleaching operation is rendered possible and a final product obtained which is remarkable for its strength, texture, and felting qualities. The use of the ferrous or other mineral protective agent'or its equivalent not only accelerates the bleaching operation but also seems to improve the carroting operation and to yield a readily feltable fiber of remarkable strength and fineness of texture.

It may here be stated that under certain conditions the combined bleaching and carroting operation by means .of a nonmetallic carroting agent may be carried out first, after which the carroting operation. may be completed by regulating the amount and length of time of treatment with the acid solution of nitrate of mercury or its equivalent. It may here also be stated that the bleaching operation may be carried out with complete success on fibers or even felts already completely carroted by treatment with an acid solution of nitrate of mercury, or equivalent reagent. In fact,

the bleaching'operation may be carried out with remarkable success on shaped felted bodies such as hat bodies, after the carroting operation has been completed. Or else such fibers, masses of felt, orshaped felted bodies, may first be bleached and partially carroted and thereafter carroted to completion as already indicated above. Other advantages of the methods of the present invention will readily occur to those skilled in the art to which the presentinvention relates, What we claim as our invention is: 1. The method of treating animal fibres and the like to render the same more suitable for felting operations, which comprises treating such fibres with a metallic compound carroting agent and with a protective agent comprising a ferrous salt to protect such fibres against excess action thereon by a subsequent bleaching agent.

2. The method of treating animal fibres and the like to render the same more suitable for felting operations, which comprisestreating such fibres with a carroting agent and with a protective agent in the form of a ferrous salt to protect such fibres against excess action thereon by a subsequent bleaching agent. I

3. The method of treating animal fibres and the like to render the same more suitable for felting operations, which comprises treating such fibres with a mercurial carroting agent and with a protective agent comprising a ferrous salt to protect such fibres against excess action thereon by a subsequent bleaching agent.

4. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a metallic compound carroting agent and with a. non-metallic carroting agent.

5. The method of treating animal fibres,

-such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with. a mercurial carroting agent and with a nonmetallic carrot-ing agent.

6. The method of treating animal fibres. such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibers with a netallic-compound carroting agent and thereafter treating such fibres with a non-metallic carroting agent.

7. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a mercurial carroting agent and thereafter treating such fibres with a non-metallic carroting agent.

8. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a mercurial carroting agent and with a nonmetallic carroting agent comprising hydrogen peroxide.

9. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a metallic compound carroting agent and with a non-metallic carroting agent comprising hydrogen peroxide.

10. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a mercurial carroting agent and thereafter treating such fibres with a non-metallic carroting agent comprising hydrogen peroxide.

11. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a metallic compound carroting agent, and with a non-metallic carroting agent in the presence of a protective and accelerating agent to protect such fibres against excess action thereon by'said non-metallic carrotln agent.

12. The method of treating anima fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a mercurial carroting agent, and with a nonmetallic carroting agent in the presence of a protective and accelerating agent to protect such fibres against excess action thereon by said non-metallic carroting agent.

13. The method of treating animal fibres, a such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a metallic compound carroting agent, and

thereafter treating such fibres with a non- 'metallic carroting agent in the presence of a protective and accelerating agent to protect such fibres against excess action thereon by said non-metallic carroting agent.

14. The method .of treating animal fibres, such as fur skins, 'hair and the like, to render the same more suitable for felting o erations, which comprises treating such bres with a mercurial carroting agent, and with hydrogen peroxide in the presence of a protective and accelerating agent to protect such fibres against excess action thereon by the hydrogen peroxide.

15. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations which comprises treating such fibres with a metallic compound carroting agent, and with hydrogen peroxide in the presence of a protective and accelerating agent to protect such fibres against excess action thereon by the hydrogen peroxide.

16. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting o erations, which comprises treating such bres with a mercurial carroting agent, and with a non-metallic carroting agent in the presence of a metallic compound protective and accelerating agent to protect such fibres against excess action thereon by said nonmetallic carroting agent.

17. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting o erations, which comprises treating such with a metallic compound carroting agent, and with a non-metallic carroting agent in the presence of a metallic protective and accelerating agent to protect such fibres against excess action thereon by said nonmetallic carroting agent.

18. The method of treating animal fibres, such as fur skins, hair and the'like, to render the same more suitable for felting operations, which comprises treating such fibres with a mercurial carroting agent, and with hydrogen peroxide in the presence of a metallic compound protective and accelerating agent to protect such. fibres against excess action thereon by the hydrogen peroxide.

19. The method of treating animal fibres," such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a metallic carroting agent, and with hydrogen peroxide in the presence of a metallic compound protective and accelerating agent to protect such fibres against excess action thereon by the hydrogen peroxide.

20. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operabres tions, which comprises treating such fibres with a metallic compound carroting agent, and with a non-metallic carroting agent in the presence of a metallic protective and accelerating agent comprising a ferrous salt to protect such fibres against excess action thereon by said non-metallic carroting a ent.

21. The method of treating animal fi res, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres With a mercurial carroting agent,and with a non-metallic compound carroting agent in the presence of a metallic compound protective and accelerating agent comprising a.

, ferrous salt to protect such fibres against excess action thereon by said non-metallic carroting agent.

22. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting o erations, which comprises treating such bres with a metallic carroting agent, and with hydrogen peroxide in the presence of a metallic protective and accelerating agent comprising a ferrous salt to protect such fibres against excess action thereon by the hydrogen peroxide. y

23. The method of treating animal fibres, such as fur skins, hair and the like, to render the same more suitable for felting operations, which comprises treating such fibres with a mercurial carroting agent, and with hydrogen peroxide in the presence of a me tallic compound protective and accelerating agent comprising a ferrous salt to protect such fibres against excess :action thereon by the hydrogen peroxide.

In testimony whereof, we have signed our names to this specification this 29th day of January, 1925.

HYMAN STEIN. IRVING LIEBOWITZ. WILLIAM E. AUSTIN. 

